There are known systems which provide billing and accounts receivable information for land-line telephone as well as cellular telephone communications. These systems are straightforward and can readily monitor the caller, callee, the time and date a call is made, and the duration of the call. At the end of each billing period, each telephone subscriber, whether based on the land-line or cellular telephone network, is provided with a bill, which includes among things an itemized list of calls made during the billing period and provides a total cost to the subscriber for the use of the telephone system and the particular communication resources.
There are also billing/accounts receivable products such as the GE-MARC V.multidot.E system manager which provide necessary software and database support (see e.g. in GE publication LBI-30337 .COPYRGT.May 1989) required to generate billing records for a single site controlled trunked rf communications system. An example of such a single site trunked communication system is disclosed in commonly assigned U.S. Pat. No. 4,905,302, entitled "Trunked Radio Repeater System" which is incorporated herein by reference. Although trunked communication systems provide much more efficient use of available bandwidth, they are considerably more complicated and therefore harder to monitor for billing purposes than land-based or cellular systems.
Trunked communication systems are even more complicated when multiple transmitting sites are established to provide rf communications to all geographic locations with a given locality. An example of such a multi-site trunked communications system is described, for example, in U.S. application Ser. No. 07/658,844, filed Feb. 22, 1991, entitled "Distributed Multi-Site Coordinator Architecture" (attorney docket 46-418), the disclosure of which is incorporated herein by reference. In these multi-site systems, prior billing systems such as the GE-MARC V.multidot.E system manager could only calculate rf usage on a per rf site basis. No capability is available to correlate individual calls and conversations to specific subscribers or a group of subscribers.
Accordingly, it is desirable that the present invention provide a billing correlation system which receives standard control messages from one (or more) multi-site coordinator(s) for all communications during a billing period for each of plural rf sites and correlates that message information into detailed records that include for each call communication at least the caller, callee(s), and rf air time used. Other desirable call specific information might also include call conversation elapsed time, conversation date and start time, rf sites involved in a call, and number of channel assignments.
The present invention relates to a method for correlating rf communications in a multi-site, trunked rf communication system including a plurality of sites ("site(s)" refers both to sites with and without site controllers) controlling mobile unit rf communications for corresponding site areas and at least one multi-site coordinator for monitoring site messages and establishing and removing rf communication channels. Information including channel assignments and channel drops generated for each communication originating from or received by each mobile unit is obtained from the multi-site coordinator. The rf communication resources used by each mobile unit are correlated for each communication based on the obtained channel assignment and channel drop information. Bills are then generated for each mobile unit detailing specific instances and types of rf communication resources used.
RF communication resources monitored for each communication include the date and time, the number of site areas involved, the call duration, the rate of service for the particular air time used, and the total cost. Specific types of rf communication resources may specify whether the communication was a voice or data communication, an encrypted or unencrypted communication, an individual or group communication, and whether it included a land-line telephone interconnect.
For communications involving a group of mobile units, bills may be correlated and provided to the group as well as to individual mobile units. The present invention correlates bills for calls generated by dispatch consoles to groups of mobile units in various site areas. Moreover, the present invention also provides specific bill correlation capabilities for mobile unit communications involving land-line telephone communications.
The method according to the present invention further includes generating call detail records for each communication based on the correlated channel assignment and channel drop information. The call detail records may then be converted into a format compatible with standard billing formats used in the telephone industry. Once converted, bills for each mobile unit can be readily generated using third party billing packages to detail the specific instances and types of rf communication resources used for a particular call.
A system according to the present invention includes plural rf sites for controlling trunked rf communications from and to mobile units within geographic site areas corresponding to the sites. A multi-site coordinator, in addition to establishing and removing rf communication channels for call communications involving mobile units in the plural site area, monitors control messages from all site regarding channel assignments and channel drops for each call communication. A correlation unit connected to the multi-site coordinator correlates rf communication resources used for individual and/or group call communications originating from or received by each mobile unit.
The correlation unit generates a call detail record for each call communication which indicates the specific rf communication resources used for each call communication. The system may further include a means for calculating and printing bills for each mobile unit and a means for converting call detail records into a format acceptable by the calculating means so that specific detailed items relating to rf usage for each mobile unit communication (e.g. the date, time, type, duration, number of sites, and total cost of each call in which the mobile unit was involved) can be included for each bill.
The multi-site coordinator includes a plurality of microprocessor-controlled nodes each corresponding to and coupled with the plurality of rf sites through a data link and a trunked audio link. An audio bus is connected to each node to convey the trunked communications between sites. A message bus is connected to each node to convey channel assignment and channel drop messages from each node. A central activity module (CAM) monitors messages on the message bus and collects in the form of raw data records those messages relating to rf channel usage. The correlation unit receives the raw data records from the central activity node over a high speed data link and converts the raw data records into individual call detail records for each call communication. A console interface node and a land-line interface node are also included for coupling call communications from a dispatch console and to/from a land line telephone network, respectively, to the multi-site coordinator.